Putting tension on shrouds

[bobsummers]

Hi Again,
This is my third email on shrouds and I want to thank everyone for the great responses. I have now serviced all 10 shrouds and 20 deadeyes on the schooner. The deadeyes now look great using a wall knot with a crown on top then whipping the 3 strands back together for a button on top of the crown and finishing the lanyard replacements with a cow hitch. Thanks again for the great knot combo recommendations. I think I can do them in my sleep now. I seem to have one last problem which is back to my original email and that is no tension on the shrouds, they are very loose. As I was servicing each deadeye and replacing the lanyard, I tried with both feet on the bulwark, leaning back and hauling, cursing etc but no significant increase in tension. I then rigged a block to the lower deadeye with a line attached to the upper deadeye, hauled on that, tied it off, rove the lanyard but when the block line was released the deadeyes would relign ( I could not get the exact deadeye alignment angle using the block) and we would be back to a floppy shroud with maybe some slight improvement. Am I missing something here or do I need to rent a come-along type device? I don't have slack in the shroud but there is no tension.
Thanks
Bob