Classic & Vintage - 27" Wheels on a Raleigh Sport?

Hi all, as it stands I currently have a Raleigh Sport, mostly classic restored. The non stock parts are stock from an older Raleigh Superbe I own as a parts bike. I'm toying with the idea of tearing down my raleigh sport and building up the superbe, then using the sport as a single speed or fixed... dunno which yet, but here's where the problem happens. I want to switch over to 27" wheels instead, I'm worried about the axle spacing and clearances though, I think I have a front fork though that wouldsolve that problem, but what about the rear? And does this really help with the clearance of the pedals and make the bike better or is this just a folklore following of doing this?

Probably clearance problems if you want to leave on the fenders.
Most hubs can be fiddled with, re: the locknuts and spacers to fit without setting the frame. On the front you may have to use the Raleigh method of "no-cone-lock-nuts" inside the fork blades, and the main axle nut outside.
A light setting of the frame usually won't hurt a hi-ten frame anyway.

The good fenders/chain guard/vintage handlebars etc would be moving to the superbe, so fender clearance won't be an issue, but I was more wondering about the rear brake stay clearance than anything else.. the fork spacing seems fine after I did some measuring. But these are steel 3 speeds we're talking about not 10 speed.. so I just want to cover my butt here.

I would guess that finding brakes that will fit would not be a problem since Raleigh brakes have a fairly long reach compared most road bikes.

I agree that the fork is likely going to be the limiting factor. I'll bet a 27" wheel fits the rear without a problem.

Neal