Im going to be building a Fiat SPA 35 and would like to depict it in N.Africa..My question is what would be the best color to use and by whom? TY!

PtvParts,
happy to see that you are going to build an italian subject. Sorry fo the delay, but I-m currently "reformatting" all of my PC...
Coming to your request, as you know we were so well organized and equipped that is quite difficult to answer your question 100% precisely.
The SPA 35 came out from the factory painted in "grigioverde mimetico" (it should be the FS34226) and Lifecolor's UA071it's the right choice. When received by the uits in North Africa, usually they were painted in... whatever color they found. So what was used is as follows:
- "giallo sabbia" (FS33434) Lifecolor UA080 that anyway it's in my view a bit too yellow but can be easy toned down adding some white or applying a filter
- german desert yellow Lifecolor UA084 (FS30400)
- 70% to 80% of Tamya XF59 "desert yellow" and 30 to 20% of Tamiya XF2 "flat white"
- after the conquer of Tobruk we got lot of paint captured to the british (unfortunately I don't know the FS reference)
Sorry not being able to be more precise, but I think that any of the above mentioned choices are correct...
Ciao

Sir I thank you very much!