I used to struggle gluing fronts. I used to glue then cut -- this is very inconsistent as glue get chipped off.

Current method is
1. Cut -- no rounding
2. Glue outside on one tire and "kiss it" to the second tire
3. Spray kicker in a cup and put both tires under it
4. Lightly sand the face to remove bumps high spots5. Repeat 2, 3, 46. Mount the tire on a TC tire spinner
7. Using 150 grit sand paper round the inside
8. Using 150 grit sand paper pass by the glue edge until you just feel a hard edge on the foam/sidewall
9. Using 1k grit sand paper quickly pass across the flat surface
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​​​​​i don't focus on running huge tires... Cars don't handle right when you so this

On crc / bsr fronts nothing bigger than 40.0mm. rear max is 41.5 --- although I usually cut spec front and rear the same size

On jaco front nothing bigger than 39.5mm. rear max is 40.5