Just a suggestion, but if it were me I would spend my next money and do the 24V starter mod. (search on here)
A new starter will be $300 plus, and you can do the 24V mod for the cost of a small second battery and mount (and relay if you go that route, or a wiring harness from Schnitz) or just some wire.
If the starter still has some life in it, that will make it work twice as good.
If the starter gives out then you have to get another (or have that one rebuilt) and you will have the 24V to apply to the new starter, which will make it work much easier.
JMO
BTW my 06 turns slower when it is hot. Seems to struggle a bit. If it gets to where you are I am going to do the 24V mod for sure.