A bit of fragmented psycho bable in my folowing post, but get yerself a pencil, draw a block on the back of a cigaret packet, and you'll get the idea.
You'll have to do the homework, but please check the Ford cataloge details and see if the ACL bearing catalogue posted by alloydave has the answers. You'll find him about five to ten pages back on this Aussie six part, and hook on to his profile, and read all posts untill you find it.
The Chev piston fits to the Ford rod with ease, its just a quality remachine and final hone out another to get the other 16 thou or so.
The Nismo Ford 4.0 Barra engine which does 1500 hp has a Precsiosn Crank Regrinders steel crank which has been reworked to run Chevy 6" rods and rod bearings. Results with a special set of Subaru style pistons with Japanese rings are sensational.
The Chev small journal and 265 Chrysler items are the same 2.0 diameter, and as near as dammit for width.
If you re grind under 123 thou or under 23 with the stock 3.91 stroke, and use small or large journal 5.7 Chevy Pink or 'O' rods and decked 60 thou over ACL Holden 253 pistons, everything should fit and handle a bizziliion revs to boot. The bore could only be 5 thou over a good stock Falcon 250 block. Rod ratios around 1.42:1 are common for the old Holden 235 strokers, and the 266 cub strokers some turbo 4.1 runner have. Drag racers frequently use these 1.42 to 1.47 rod ratios. In addition, the ACL piston is a piston of almost 265 Chrysler type which can hack 6800 rpm in a little 253, so 5500 rpm in a 250 isn't out of the question. The right Chevy rods are almost as good as the stock 5.75" 265 Rod. If you've got a thick 1.77" deck piston like the 265 and 253 have , you can use nitrous or 18 pounds of boost, and not risk loosing pistons. Forged pistons are not mandatory. Plenty of turbo red engines and the occasional Ford run ACL cast pistons, and a few of those have done low 11's with over 18 pounds of boost.
I've got a 5MA 221 crank in my 56 thou over 250 X-flow, using the stock forged TRW 229/305 Chevy pistons and 200 conrods. Rod ratio is 1.81:1, but you loose 29 cubes. The engine is being saved for another project, but it's not worth the money doing the remaching unless the parts are dirt cheep, and you end up with better rods, pistons and a beeter crank. I'm sure when I do get it the recmachined engine out of the old bath its been sitting in since March 2003, it'll be a lovely sweet reving street engine that will always be 13% and 29 cubes smaller than everyone elses 250 Falcon.
If you do your homework, you can do anything. Sounds like your budget minded, so for every dollar, I'd recomend the Holden V8 challange pistons, good stock length Chevy rods, and tie it all to a reground crank. There is no problem with using an EF or EL crank taken down to even 2.0". They are strong enough for 6000 rpm.
