Jonathan, You've got the right names when it comes to building big engines. Bud Clark's number is 714-282-7378 (No e-mail). Consider too Tom Donney and Chip Lamb (Follow the links page or go through their individual pages on SaabSpot).(posted 8858 days ago)Can't hurt to tell 'em I sent you.
RE tire question: Join the VSAAB list! It is filled with Sonett guys who have centuries of experience!
Best of Luck,
Dennis O'Connor Webmaster