tyre size under the back of an xd/xe/xf is a myth. i know of cases with just removing the lip on the guards, with the right offset you can squeeze 275 and even a 295 under the rears.
as for tyre size on a 8" rim, a 225 goes on ok as i have a set of dragways here with 225 on the 8" rears and they are fine. admittedly it could be a little wider, but tyres are cheaper and easier to find. i was running kumho power max and they grip well in both wet and dry. as for front sizes, good luck getting a 235 on a standard offset rim to work. unless you use the same offset rims as a pre au 16's or 17's they will scrub the outer lips. i have had trouble with 215's on 7" rims on the front, especially if its lowered.

tony 235's will go ok all the way round on mine as my rims are a different offset and will take the larger tyre without hitting the gards i have 215 all way round now and have plenty of room for upsizing but iv just come across some mags i want for it that used to be on my xf the offset on them is fine to take 245 on the front and 265 on the back thats what it was running b4 with know drama's but id rather go same size all way round as for rotating but then again dont know still deciding

got any picts of the old gal