I'm assuming that this is supposed to be Ireland? Maybe a roadster, like a Bently or an Aston Martin. Didn't James Bond drive a silver Aston Martin DB5?
Depending on the year, in this case the late 1970s, gold would be an appropriate choice. I've found that Tamiya Gold Leaf X-12 is pretty close. The 300-Plus ETAZ-673A was copper colored.
You're logger looks really nice. I like the subtile weathering, and the details. That dash is really pretty (I didn't think I'd ever say that about a Paystar). Excellent job so far.
Oh, that's right! On the 3406 the oil pan is molded onto the block. Forgot about that. I'll have to give it some thought. We just might have to get creative.
Yes, the V800 was blue. All other engines the International put into their trucks at their time were International 2150 Red (apparently Testors Red 1203 is a good match), but they wanted this one to "stand out". I'm not sure when International switched to OEM colors for the other engines that were offered in their trucks.
The engine that's in the International 4300 is the International V800. I've heard that Testors Model Masters Auto Laquer Metalic 1969 Ford Acapulco Blue is pretty close.
Here, this article might help: Detailing the International V800. Well, it couldn't hurt, anyway.
The AMT/Ertl/Esci Kenworth Aerodyne are all the same kit. They are based on the Tyrone malone Papa & Hideout trucks, so they have long frames & the Kenworth 8-bag air ride suspension.
So far, so good. What's your "ultimate" plan with this? Reason I ask is if you're thinking fleet truck, stick with the Series 60. If you're thinking Owner-Operator either engine will be fine.