Hi the amps are shown in the posts there are 2 links to them.
You should only use a 8 ohm speaker with the amps
Also you put more strain on the rx18 amp if you have to always have the volume contole real high this is why you should hook it up the way i say and use the amps with the adjustable volume control on them this way you set the HL tank VOL not so loud and use the amps volume you don't want to crank the HL volume up past half way to 3/4 it will then just make your good amp amplify it's distorted signal so it will sound worse than stock.