Can a guy run gen.1 wheels for the track,(road course), with a gen 2???
Not necessarily - Depends on what year Gen II.
18" wheels were introduced on normal production Vipers in 1999 (earlier on the GT-2 - '98?), but the brakes/spindles were evidently unchanged until 2001 when ABS was introduced on the Gen II's. I've been told (i.e., I don't know this for a fact personally) that 17" wheels will not fit on the 2001 and 2002 ABS cars. Evidently the ABS cars have one bolt that interferes with 17" wheels, and has to be shaved or otherwise modified. Like I said, I've not confirmed this (I don't have an ABS car) and don't know whether its all four or just two (or one) of the corners that has the interference.
Personally, I use a set of 1997 (17") five-spokes on my 2000 (18" stock wheels) for track tires. This combination works without any problem. It also has the advantage that the 17" tires are slightly cheaper.