71/2 have a V8 K-frame. Same for SB and BB. 73/4 is a totally different frame than 71/2 and also has a SB and a BB frame.
So in your 72 if you want to change the 318 with a 440 your good to go. Just need some BB motor mounting brackets.
66-72B
66-73C
70-1E

72 Satellite Sebring Plus 440, 72 Dart 5.9 4-spd, 68 Valiant, 73 W200, 78 D100 sb, 78 D200, 98 DAKOTA, .
Moparmarks Parts & Restorations
Desert Mopar Metal
Grand Jct. CO
970-261-7039
http://moparmark.com/
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