Soon to be 63 GMC owner.

[creep]

Hey guys (and girls?). I'm buying a 63 GMC 3/4 ton longbed 2WD from my buddy's uncle. It has 305 v6 with plaid valve covers, a 4 speed manual, and posi rear end. I have some questions that hopefully won't sound too stupid as this will be my first classic.

1. Can the 305 be modified to run on regular gas with out the lead additive?
2. Does anyone know the story behind the plaid valve covers?
3. Can drop spindles for a 1/2 ton Chevy be used on a 3/4 ton GMC?
4. What's the best way to switch to a 5x5 lug pattern (switching from 8 lug)

That's all for now. Thanks in advance for any and all future help.