Most respected/honest maintenance shop around town is still Scotty's (Stanford Auto Centre - Stanford Auto Centre Inc | Car Repair Parksville | Home
) in Parksville as far as I know. You'll need to book ahead to get in. I don't know how good they are with performance cars personally. I've only gone in with my daily drivers.
Miles D Automotive is involved with the local car clubs and my Dad's trusted him with his '39 Chevy. Looks like he works on a lot of vintage and hot rod cars: Auto Maintenance & Repairs Qualicum, BC | Home | Miles D. Automotive
Been a couple years since I've been in the area with a fast Dodge.
I'd say someone else may chime in with better info but this forum is pretty dead now.
Manic! is still active though. He would have better info than me for Nanaimo.