Shell - sides and back
The back of the locomotive needs to have the incorrect style of dual-pyle backup light and corner marker lights removed and their locations filled in with putty and sanded down. As well, the rear square sand hatches are in the incorrect location and will need to be lowered. Do this by filling old hatches with putty and sanding, then cut new squares below the old hatches. For the sides, the engine room door needs to be moved back. Do this by resin casting a section of the body from a scrap shell, cut out the offending door (see photos below) and carefully file/sand down the notch to ensure a snug fit for the new resin carbody casting. After this is done, you should have a narrow section of carbody (between batten strips) over which the new engine access door from the Kaslo fret should be glued. Putty in the original two railing mounting holes that are now above the new carbody section. There are small dynamic brake access panels along the upper edge of the locomotive about 1/3rd of the way back along each side. Depending on which shell (ie. Kato or Walthers) you are using, check prototype photos to see which style of panel your chosen road number uses, then cut these from the Kaslo fret and glue them in place. Both sides of the locomotive should have same style of panel. Add two knucklebuster latches to each side as shown in the photos below.
Walthers grille replacement
If using Walthers, consider replacing the radiator, dynamic brake and air intake grilles with S&S Products #308 grilles as shown in these photos.
Shell - cab
The cab is one of the most time-consuming and labour intensive parts of this kitbash. A lot of inaccurate details need to be sanded or filed down including the entire side of the cab up to the door and under the side windows, roof and front. After all filing of unwanted detail is complete, assemble the stacks of 4 thickness plates from Kaslo HD-41 fret (but not the top plate yet) and use as a guide to file out a square under the cab door on each side of the unit. Take your time and file carefully as the plates should be a snug fit. Walthers brake and sander access doors have deeper notches that will require a few applications of putty filler and lots of sanding patience. Also putty in the cab rooftop center notch and sand until all evidence of the notch is gone. Remove and fill the incorrect marker lights at the same time. Carefully ream out the original factory side grab iron locator holes with a pin vice. When all sanding is complete (take your time so you get a nice smooth finish on front and sides), glue in the cab step assemblies (note .005 styrene backers), new numberboards, tri-colour corner class light brackets, brake access doors, rain gutter, sander access doors and discs, new cab doors (I prefer to glue these over the existing door) and new corner cab window, all from the Kaslo fret. Add Sinclair antenna. Ensure all sanding and filing is perfect before adding new parts, then allow to dry prior to priming and painting. For Walthers cab stirrups, file down the sides of existing stirrups (DO NOT remove them) to square them off, then glue the new stirrups over the existing ones. The cab interiors need some Rapido caboose seats and simple desktops made of styrene. Paint the entire piece brown after the glue dries.
Shell - roof
The roofline is another time-consuming and parts-intensive section. As with all other elements of this kitbash, take your time and ensure you have all the parts and tools needed beforehand. Moving backwards from front to back, the cab roof, inertial hatch, exhaust hatch, dynamic brake fan and all three radiator fans need to be removed as they are not a good representation of VIA features. Remove all unwanted details first before adding replacement parts. Remove all of the cab roof cast-on details (as shown in photos above) and fill all holes with putty and sand the entire cab roof smooth. Next, replace the inertial hatch with the new Cannon FH1358 part (this appears to be a closer match for the VIA component) and carve off the incorrectly-located Cannon vent. According to prototype photos, there are two sizes of .005 styrene square hatches that need to be added. Cut and glue in place and then build a .015 base for the new small air vent (part 33 from the Kaslo fret). Glue to the top side according to the prototype locations shown elsewhere on this website and as shown below. Next, rebuild the exhaust hatch out of .040 styrene and carve out a notch for the new exhaust stack (part 30 from the Kaslo fret) as shown below. All of the cast-on fans on your model sit in in incorrect depression and need to be removed (I ream them out with a Unibit). For the dynamic brake fan, measure, cut and install a new styrene fan base plate. When satisfied with the new base plate, install the Detail Associates (DA) or other dynamic brake fan. Then ream that fan out and leave only the outer perimeter as shown below. Add nice new Plano fan top and blade parts inside the DA fan circle. Moving backwards again, modify the radiator fan plate (Plano part #185) and glue over the radiator fan area. When dry, glue the MBE hatch, eye pins, MBE H34 horn and two new Quiet fans in their holes.