If you are going to run solid lifters either roller or flat tappet just leave it there. It helps to keep some oil off the crankshaft and if it spits a lifter out you will still have oil pressure. Otherwise you could remove the plug for the left side galley and drill the tube in the right side lifter bores to get oil to the lifters. Removing those tubes, (there is usually two of them, one inserted from the rear and one from the front) is going to be a real bear. Not sure how you would even get them out except to maybe drill them and that would be a huge pain once they were peened in the lifter bores.