8T1-7T9 BIONIC VETTE

The Mid America Catalog says to measure the front yoke.....is it 3 1/2" or 4 1/4"???????......Ordering new 3:73 rear end......should I replace the half shafts too? :confused: What else?????? since I'm in there.... Mid America will only refund $150.00 of my $300.00 core charge since my gears are not the same as the ones I'm ordering. Anyone here in Hawaii need a good pumkin with 2:88 gears let me know...... :seeya