Hi Peter, Welcome to the site.
As Glen suggested, going with one of John Mummerts stroker kits would simplify things quite a bit.
Offset grinding will automatically reduce the journal size which requires a different connecting rod. Some of the options on offset grinding for the Y are to grind to a 2.100”, 2.000”, or 1.889” journal. The 2.000” journals for the Y seem to be the norm for any kind of significant stroke increase over stock.
As long as you’re using custom pistons, almost any available scrub (SBC) 2.000” journal rod will work for you. Eagle has quite a selection of H-Beam rods in the aforementioned 2.000” journal size ranging from 6.125” to 6.300” long with the pin bushings being sized for the 0.927” wrist pin. The 0.940” scrub rod big end width would need to be trimmed down to accommodate the Y-Blocks journal width with the majority of this material needing to be taken off of the inside rod face rather than the crankshaft journals radius side. A small amount of this additional width can be taken up by doing some widening of the crankshaft journals while doing the offset grinding. If offset grinding the 272/292 crank to a 3.48” stroke with a 2.000” journal, then a 6.200” scrub rod with the piston pin itself being in the stock Y location is doable with a small amount of machining to the block deck being required to get back to a zero deck clearance. You’d still need to use a 0.927” pin in the piston though if using a scrub rod if you're not in position to rebush the rods for a Ford sized wrist pin. But if going to a custom piston, then by all means optimize the compression height (wrist pin location) to minimize the amount of milling that would need to be performed to the deck surfaces.