Jonathan asked me to address the question of what an A176 mount bar fits. Here goes...
-200/300 series Poulans. 245A. 306A, etc.
-360-451 series Poulans. 361, 401, etc.
-3400-4000+PoulanPro 375/385/395 series saws.
-4200-5400 Poulan CounterVibe saws with 5/16" studs. Some 4900/5400 saws have 3/8" studs (and would instead take a D096/D196/UXL/TXL mount)
-XL series Homelites with 5/16" bar studs. 1960's production XL-12, XL-15, XL-Automatic, Super XL-12, XL-400A, XL-500, XL-600 series, XL-700/800 series, etc.
-Many old Echo saws from the CS451VL through the CS-802.
-Current Echo 670/6700/680 and 800/8000 series saws.
-Lombards that look like an XL-12. Comango, AP-42, etc.
-Roper 3.7ci saws, including the various Craftsman branded versions.
There probably are more 1960's/1970's saws that can use this mount. Some as-is, and some with a little modification. If a fellow milled the slot from 5/16" to 3/8" they could use these bars on the many D096/D196/UXL/TXL mount saws out there. If they milled it to 9mm they could probably do the same with large Husky D009 mount saws (so long as the oiler and adjuster holes match....YMMV). Milling the slot to 10mm would allow use on D024 (old Jonsereds) saws.