I am thinking about getting Vintage 48 16x8 wheels, which have 4.5 backspace. Would I have any problems with 245/50/16 tires all the way around on my 69 which has the Hotchkis suspension?

I have the V45's with 255/50-16 on the rear and Hotchkis springs. 245/50-16 on the front with Global West springs. You may need some negative camber on the front to tuck the tire inside the wheel well as well as some button head bolts for the top inner fender.

With 17s or bigger the perferred backspace on an 8" wheel is 4.75". I think that would be better even though it's only a 1/4". You can always use a small spacer to bring the wheel out "a little" but you sure can't go the other way without going to a smaller size tire. The 245 is going to be tight in the front as it is. Can you try something close 1st to get an idea?

Thanks guys.

That's exactly what I'm running on my '69 now (V48 16x8 w/ 4.5" backspace, 245-50R16 tyres on all 4 corners). Running an "aftermarket" factory-style disc brake kit and the guildstrand mod. I thought I had my alignment specs printed out, but can't find them -- something like -1 deg camber an 4 deg of castor. I'm running the Hotchkis springs front and rear, but also running spring rubbers up front and custom shackles in the rear, so my ride height is tweaked (top of tyre is even with w/w opening)

Anyhow, clearance to the frame at full lock is good (1/4" or so?) but I just barely touch the outside corner of the tyre on lowest rear w/w molding bolt -- not sure if that's due to the castor I'm running or if something is "special" in my suspension (driver side doesn't seem to rub, pass side does?) Going to change over to stainless button head bolts for the rest of the w/w molding fasteners and it should be fine.