The nose is generally the only difference so you should be able to make one good one out of the two. Keep in mind that all starters are not created equal in that there are standard and heavy duty versions. A good rebuilder can spot the difference but many parts stores don't know. If you have to get a replacement, ask for the HD. Also go back and clean all of your battery and starter connections. They can also be a source of your problems.
Fred


1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine