Iowa Interstate's Iowa City yard was visible from my college apartment for three years, which inspired me to model the RR, including a pair of HO GP38s (from Athearn GP38-2s) I finished back in 1990. With the release of the Intermountain GP10s I decided to update those GP38s with DCC and better lighting while finishing the GP10s so I could weather everything at the same time.

GP10 451 & 484
- cut loops off of cut levers, touched up cut area with yellow paint
- added DA small Sinclair antennas painted aluminum
- added DW -364 speed recorder painted black
- removed ditch lights and filled holes on 484, painted finished area black
- removed stock can antenna (too large) and replaced it with DA part, painted black
- installed drop steps in down position
- removed stock windshield wipers and replaced them with A-Line parts, painted black
- replaced stock couplers with Kadee 58s painted Model Master Leather and dry brushed with a dark brown

GP38 601 & 602
- these started as Athearn blue box GP38-2s, so removed cab overhang, filled water sight glass on long hood and changed sideframes to Blomberg-Bs.
- these were originally completed in 1990 and I wanted to bring them up-to-date with DCC and working lights (originally completed with MV lenses)
- parts added originally: DA MU Hoses, DW -190 air horn, DW -157 Firecracker antenna, eye bolts, grab irons, DW spark arrestors, custom made MU stands, DA cab sunshades (hinged with eye bolts so they operate), DW fuel fillers, DA fuel sight gauges, DW air filters, DA underframe bell, Cannon & Co. angled paper air filter box
- I added DW -364 speed recorders as part of the update

Weathering
- all clear items were masked (lights, windows, numberboards) – with masking removed at the end of weathering
- I sprayed the roofs with an acrylic flat black that is the equivalent of a weathered black, then spot sprayed areas of the underframe, pilot, trucks and fuel tank
- I then dusted the walkways and top of the noses with light gray, then medium gray weathering chalks, then dullcoated to seal the effects
- Using the light gray I went over areas of the trucks – some sideframes were dusted completely, some had only portions done
- I created a semi-gloss “oily black” and sprayed around the spark arrestors
- I then airbrushed Model Master Skin Tone Dark Tint on the pilots, ends of the fuel tanks and at various point around the rest of the area below the walkway to simulate mud and dirt
- Next up was airbrushing Model Master light gray sparingly to create highlights and blend some of the other weathering
- I used a light sand color chalk to create the effects of freshly spilled sand on one of the GP38s by the rear sand fill