I ran into your problem a few months ago. The replacement wheel cylinders around have 2 different length handbrake arms. There is a statement somewhere on the TRF sight that either will work, but you must have the same length on both sides...so no mixing and matching.
My 9 inch brakes came with 2 different style springs. I ordered a couple sets, but as you noticed, they were too long. I wound up re-using the originals in the end. The correct springs are extremely difficult to stretch during assembly, so I suppose you know you have the correct ones when that is the case. I looked for pictures, but don't have any decent ones. Here are some that relate...

You can just make out the upper spring in this one. It has a straight run in the center to avoid scraping the cylinder.

An original brake shoe design. There are many variations...I had to return 2 orders when they were mis-advertised by both ebay sellers AND one of the big three. They are getting hard to find. TRF still has them, but even they sent one 9 and one 10 inch.

The original style handbrake lever.

The new handbrake lever...about 1/4" shorter than the original.
Oh, worth mentioning...the handbrake levers can be swapped from your original cylinders to the new. Mine were too corroded to re-use, but something to consider.