Don't attach the ground cable at the battery on either vehicle. Use the engine block, cylinder head, alternator mount, etc. That way, if a spark happens, it's away from the battery. Connect positive to positive at the battery, then do the ground cable last, on a chassis ground somewhere. I have blown up batteries, and it's not a fun thing to do!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!