you MIGHT not need a change as far as the setup but you might need additional filing on the nut side of your guitar since 42 and 52 low E sizes are very different. after this is done, check your intonation by comparing the 12th fret harmonics with the fretted notes on every string, after you bring the strings to tune at standard 44.1 concert pitch. this will tell you just how well your guitar accomodates the new strings AND how much you will have to adjust the bridge and truss rod. your guitar, being a telecaster, is more resistant to bowing than say, a set neck les paul bit still, checking will make sure you stay in tune.
reggae music calls for an accented pick attack so you can use a compressor in front of your amp and set the sustain to moderate but the attack slightly higher than 12:00 - maybe less - depending on the charcteristics of your amp. you can also put a short delay to add a little bit of tail to your barred notes. since reggae chords are syncopated, the delay will fill out the gaps in your picking making the bars of the song more dynamic - especially if you're the only guitaist in the band.