There will be no increased labor charges in replacing them, that would be included in your guide replacement. Spend the money and buy the tensioners. From what I'm starting to think you aren't replacing chains either. The tensioners ratchet out with oil pressure and chain stretch. Depending on the amount of chain stretch you have on the chains, if you're reusing them, the tensioners may be locked out at their limits already and there would be no need to replace them with new units that will lock out on first crank.
Don't take this the wrong way, but if you're not willing to do it the right way and replace the components that work together in the timing setup why not just wait until you have the money to do replace it all? I know it's not cheap, but it's a lot cheaper than paying for it today, then paying for it again in 5k miles plus more parts to do the job that should have been done originally. To each their own, but if I'm going into the front side of the 4.6 it's getting chains, tensioners and guides. No increased labor cost to install them.
03 Silver Fauxbra; 06 Legend Lime GT, 89 Outlaw 10.5W Coupe, 93 Teal Cobra, 93 Red GT, 93 Teal LX
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