I've been going through the same thing. So far I've come up with two options: If you only need it for one or two projects in the immediate future, you can download the thirty day trial of Autodesk Impression and use that, but as you are on AutoCad LT you will not be able to purchase a full license--it is only available to full AutoCad subcription members. The second option is to import your drawing into Sketchup and manipulate the Styles until you get the line styles that you want. Line weight is an issue with this approach, as Sketchup treats everything the same.
I am looking into the latter approach then importing the PDF file into Autodesk Sketchbook Pro for color/rendering. I'll let you know how that goes, but if anyone has any other ideas I'd love to hear them. I am also on LT and thought I could finish my renderings in thirty days with Impression, but failed and am now out of luck. I can't justify the $4k pricetag for full AutoCad at this point.
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Mary Holley AIA
President
Mary A. Avjian Architect P.C.
Basalt CO
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