This is a easy DIY. A HD touring bike service manual for your year is recommended.
1-Pull fuel tank & spark plugs & pushrod tube spring cap retainer
2- take bolts out of rocker covers and remove rocker covers.
3- take bolts out of crankcase breather with 3/8 socket and ratchet there is no need to remove breather from rocker housing.
4- rotate engine until the cam is on the base circle, you can do this by bumping the starter and looking at the rocker assembly at the same time.
5- loosen the 4 rocker bolts using 1/2 inch box end wrench. Alternate loosening the rocker bolts until the tension from the pushrods & lifters is off the rocker assembly.
6- With the rocker bolts completely loose you can lift the rocker assembly and rotate the rockers 1/4 of a turn than you can pull the pushrod right out of the top of the engine. It is best to mark the pushrods intake and exhaust for installation later on.
7- with the pushrods out you can pull the right side rocker bolts out of the rocker assembly and you leave the left side rocker bolts in the the rocker assembly and then you can remove the rocker assembly bringing the assembly out on the right side of the engine.
8- remove rocker box bolts using a 7/16 wrench and remove rocker box.
You can reuse the gaskets if there is no damage to them but new gaskets don't cost much. Also it is hard to get a torque wrench in some places so remember that the bolts are threaded into aluminum and it is easy to strip the threads if you over tighten the bolts, just snugging up the bolt good will be tight enough in most cases.
Installation is easy, just start at 7 and go to 1. This would be a good time to install adjustable pushrod in if you do just follow the instructions included with the pushrods to adjust.