I check my oil about 20 minutes after shutting down. You want it to have time to drip down into the sump.
For gas, use whatever you like, as long as it doesn't ping. Harry Pellow, (considered to be a 356 god) liked whatever Chevron was passing off as "gas" in California.
You may also want to subscribe ot the 356 Registry's (
www.356registry.org) listserv 356Talk.