65 Manual Brake Light Switch Replacement

Hello all, been quiet for a while, but could do with a little help please.
The brake light switch is defective and needs to be replaced on my 65 manual coupe. Been wrestling with this for a few days, off and on.......it's a swine.
The old switch is out, had to unloosen the M/C a tad, but the switch is out.
To install the new switch I'm supposed to use two spacers, one either side of the switch, but I can't install two, the pedal shaft isn't long enough. I can only install one. I've read some links that suggest that this is a common issue, inability to install both spacers. When I took the old switch off, it had one spacer on the outboard, left hand side, next to the hairpin. If I can only install one spacer, which side should I put it on. Both sides of the switch are going to see relative movement, I'm thinking that the right hand side might be best though.
Also, having real problems getting the hairpin in, access is terrible, and there's a generous chamfer on the shaft end, which might mean that a hairpin may not be effective. Any tips on getting this sucker in, or alternative cotter pins, etc. would be appreciated. I'm even thinking of dropping the steering column, but I don't know if this is necessay, or what is involved with this.
Thanks in advance.

Managed to install my new brake light switch at the weekend. Actually the installation went very smoothly, once I’d done a few dry runs. Access for this project is very bad. I did a lot of reading and trawling the internet on this subject. It appears that I have the brake pedal with the shorter shaft, this made it impossible to install both the 0.1 inch thick nylon spacers. The PO had only installed the one spacer at the hairpin end. I had read that without the spacer at the hairpin end, depending on how tight the stack is, the hairpin can wear into the switch chassis. There will also be relative movement between the switch and the pedal, so a washer at the other end would be desirable. I wanted to find a solution that had two washers, but thinner than the nylon washers. I had also read that if the stack is either too tight of too loose the switch may not operate. After a trip to Ace I found two hardened steel thrust washers, 0.05 inch thick. I ground the inside diameter to fit over the pedal shaft, one each side of the switch in place of the nylon washers, these were the right thickness for my application and will be hard wearing. I secured the stack with a new hairpin. Seems to work fine, took the old girl out for a ride on Sunday, no issues. I will be doing ‘pre-flight’ brake light checks at least for the short term, until I get confidence in the fix.
Some more advice. Although you are supposed to be able to install the switch without removing the M/C rod, access is so bad that I opted to loosen the M/C on the firewall to give some more ‘wiggle room’. I spent $7 in Ace for a multi LED battery light source, this was very helpful. I also had issues holding the hairpin with pliers and locating it in the hole in the shaft. A quick trip to Harbor Freight and I was able to purchase a pair of long hemostat clamps. The hemostat, is a medical clamp and has handles that can be held in place by their locking mechanism. The locking mechanism is typically a series of interlocking teeth, a few on each handle, that allow the user to adjust the clamping force of the pliers. These were cheap and very helpful in getting the hairpin in place. Driving the hairpin through the hole the spacer got misaligned, cocked, just enough to prevent the hairpin from passing through the hole. I was able to file a chamfer on the hairpin which had the effect of pushing the washer back into alignment and allowing the hairpin to pass.
As I say, because of the seriousness of potential brake lights failing I will be checking their operation before each trip, at least for a while.
Thanks for all the help guys.