There is a short circuit (a connection between hot and neutral) in that gi loop. It doesn't just happen by itself, think about any changes or work you did since it worked last. Check that area first. Get yourself one of these circuit breakers and clip it across the fuse holder.
TE Connectivity W58-XB1A4A-3 Circuit Breaker; Therm; Push; Cur-Rtg 3A; Panel; 1 Pole; Vol-Rtg 250/50VAC/VDC https://www.amazon.com/dp/B00DECRYG4/ref=cm_sw_r_awd_R72owbN4Y1SDF
The one I linked is rated for 3A. Make sure the circuit breaker is rated equal to or less than the correct fuse size. This way you won't burn up a bunch of fuses while troubleshooting.
I usually start by marking the affected sockets under the playfield with blue painters tape so I know where to focus. With the machine off start at one end and try to eliminate anything obvious with a thorough visual inspection like bent tabs, alligator clips, etc. in that gi loop. If you find something suspicious, make that correction only then turn the machine on to test. Don't leave the machine on if it trips, turn it off quick to avoid more serious damage. If you don't find anything obvious, go back and remove the socket and bulb one at a time. Blow the socket out with compressed air, look for something that might have fallen in the socket, etc. Test each time you do this until you isolate the problem.
This has always worked for me in the past. For me it was usually a socket short I caused when replacing a gi bulb. One time I put in a new LED bulb that was longer and had a metal ring around the face which was extending up through the playfield and touching a metal lane divider (took me a while to figure that out!) If you go through each socket thoroughly and still blow a fuse, your problem is in the backbox and I wouldn't know how to help you there.