99.9% sure expecting 5 years on the tek (supercrap) actuator will make you the laughing stock.
I can't believe the headache from just buying a replacement motor I just had.
These things are out in the weather. If you don't do periodic maintenance on them, which 'who' used to back in the heyday, they will.
Of course you will get better arc with a longer actuator. Just make note where dish flop happens. You might even be able to move the the actuator mounting point out more towards the dish rim with a little creative fabrication.
That itself would lessen the actuator load plus increase your counts/degree of arc.