I won't swear it's correct, but my starter cable comes off the solenoid going to the right, so it passes to the right of the choke cable, and is held by a tab on the body shelf along with the main harness.
On the choke cable, did you get the "original type" 734-015 or the "replacement" 331-080?
Personally I like the "replacement" I got many years ago better than the stock cable. Doesn't take the original knob, but with a little careful sanding, the fixed knob is almost the right profile. And I really like the locking feature that will lock in any position rather than just at a few discrete steps. I did have to replace the little metal piece that does the locking when I moved it from the wrecked 3A to the 'new' TR3, but just the fact it's still working some 25 years after I bought it is impressive to me.
If it's too long, then I would definitely suggest cutting it to the right length. A Dremel moto-tool with an abrasive cutoff blade works well.
https://www.hobbylinc.com/htm/dub/dub353.htm
Pull the inner cable back while you cut the outer cable, and trim away any burr. Then wrap some masking tape tightly around the inner cable, and cut through the tape. As always, be sure to wear eye protection.